adding clearTimeout on stop, thus forcing avoiding the call of reconnect

Hi ! Using the stop call in https://github.com/ttezel/twit#streamstop I've noticed that the reconnect function was keep called. 
I just added a variable that save the timeout call and clear it when stop is called. I've tried to break on : 
https://github.com/ttezel/twit/blob/master/lib/oarequest.js#L152

But sometimes it pass this condition. 

I perfectly admit this is a hack, but anyway, it might help someone.